Paper tube and process of waterproofing the same.



H. C. PRITHAM.

PAPER TUBE AND PROCESS OF WATERPROOFING THE SAME.

APPLICATION FILED MAY 28, 1914.

1,174,279. Patented Mar. 7,1916.

WITNESSES: 1w

M M By UNITED STATES PATENT orrron HENRY c. running; or rmearonr, cozmno'rxour, assmnon 'ro union mE'raLLIo cmrmon comm, or nmonroar, connmc'rmur, A conrona'rron or con- NECTICUT.

Specification of Letters retent.

Patented Mar. '7, 1916.

Application filed Kay 28, 1914. Serial No. 841,494.

To all whom it may concern:

Be it known that I, HENRY C. Prrrnam, a citizen of the United States, residing at Bridgeport, county'of Fairfield, State of Connecticut, have invented an Improvement in Paper Tubes and Processes of Waterproofing the .Same, of which the followlng is a specification. In the accompanying drawing forming a portion of this specification, the figure is a representation of a paper tube in perspeca smooth and even surface; that the tube shall be waterproof, and also, in order to make it a salable and attractive article, that the color shall appear the same, or substantially the same, over the entire outer surface of the tube.

The object of the present invention is to produce such a tube, and by employing the process hereinafter set forth, such object is accomplished.

Paper tubes are usually made by rolling a sheet of paper into tubular form and sticking the same, so that it retains its tubular shape. In order that this may be easily accomplished, paper intended to be made into tubes is usually made uncalendered or nearly so. -It will be seen that such tubes will be very sensitive to atmospheric conditions, absorbing water easily, and changing their diameters according to the amounts of water absorbed. In order to prevent this, such paper tubes are usually first brought to exact size by being passed through a suit- I able ,sizing die, which also tends to put a in the case of colored tubes, more or less translucent at different places, and hence blotchy or mottled.

I have found by repeated experiments that paper tubes treated by impregnating or coatin with a small percentage of a polymeriza le oil or a solution .thereof in molten wax, and in which the polymerizable oil is thereafter gelatinized by any suitable means, are waterproofed in a superior manner and donot show the mottling or blotching usually found. A composition preferably employed for such waterproofin purposes consists of tung oil, otherwise own as Chinese wood oil, dissolved in molten parafiin wax in proportions of three parts of oil to ninety-seven parts of molten parafiin wax. It should, however, be understood that my invention is not limited to the specific use of Chinese wood oil dissolved in parafiin wax, but other polymerizable oils may be used, and the composition of the waterproofing and the proportions of the ingredients may be varied to suit special requirements without exceeding the scope of this invention. Tubes, so waterproofed, are heated to a higher temperature than that of the bath in order to drain oil the excess of wax and thoroughly polymerize and gelatinize the oil contained therein.

By employing tung oil, or its equivalent, dissolved in paraffin wax, the waterproofing material is not only caused to fill the interstices between the fibers of the paper, but also actually fills the capillary openings in said fibers.

Having thus described my invention, I claim:

1. The process of waterproofing paper tubes for cartridge shell bodies which consists in impregnating the tubes with a solution of a polymerizable oil in a molten wax which possesses lubricating qualities, and thereafter heating the tubes in order to gelatinize the absorbed polymerizable oil.

2. The process of waterproofing paper tubes for cartridge shell bodies WhlCh consists in impregnating the tubes with a solution of Chinese wood oil in a wax which possesses lubricating qualities and thereafter heating the tubes in order to gelatinize the oil contained therein.

3. The process of waterproofing paper tubes for cartridge shell bodies which con- Q sists in impreg'nating'the paper tubes with a solution consistmg of three parts Chinese wood oil in ninety-seven parts of paraflin wax, afid thereafter gelatmizing the Chi nese wood oil contained'therein. A. As a new article of manufacture, a paper tube for cartridge shell bodies iwater-- proofed with a pol-ymerizable oil and a wax which will act as a lubricant, the polymerizable oil being gelatini'zed therein.

5. As a newiarticle of manufacture, a paper tube for'eartridge shell bodies water-- proofed with Chinese wood oil and parafiin wax, the Chinese wood oil being gelatinized therein 6. a new article of Inanufacture, a' pa;

pertifo'e for cartridge shell bodies having a whereof I afiix my signature 

